As far as the question of responsibility for plastic bags, it must lie with the originator of this convenience; the supermarket. For one thing it is not the supermarket customer that demands that these bags be made of plastic! The customer only requires an instant no charge bag to carry away his shopping at check-out.In a perfect world the customer may dream that the supermarket gives them a free bag. However, it is the supermarket which decides to use the cheapest, possible plastic bags with their advertising.